It is known that a semiconductor chip having an array of terminal pads on a chip surface is mounted on a printed circuit board or another semiconductor chip also having an array of terminal pads by flip-chip method, wherein the arrays of terminal pads on a chip are connected with each other by vertical solder bump interconnections between a chip and a printed circuit board or another semiconductor chip. For typical processing, solder bumps are transferred from a solder bump transfer plate to each of terminal pads on a chip surface. Solder deposits on a solder bump transfer plate are usually formed on a glass substrate by vapor phase deposition with a metal mask or by selective electroplating method. Generally, as packing-density of integrated circuits increases, both size and space of terminal pads are needed to decrease, from which various technical problems arise, such as solder bridges connecting between adjacent terminal pads causing short circuits between the terminal pads, or non-uniformity of the amount of solder applied, per pad, causing electrical disconnection of a vertical solder bump interconnection. Solder deposits, which are predecessors of solder bumps, on a solder bump transfer plate formed by vapor phase deposition through through-holes of a metal mask are often detached from deposited sites when the metal mask is separated from the solder bump transfer plate, because the solder deposits are often adhering to inside walls of the through-holes. In Japanese Laid-open Patent Application No. 5-235003, a method is described that an inside wall of a through-hole of a metal mask is lined with material having non-wettable tendency to molten solder. In this method, however, repelled solder is solidified around a solder bump, in cooling, as solder bridges or solder balls which often cause a short circuit between adjacent terminal pads.
A solder ball is usually produced on a surface of a semiconductor chip between terminal pads from an excessive amount of solder extending to the outskirts of a solder deposit, deposited on a solder bump transfer plate using a metal mask when the solder deposit is melted, so as to transfer onto the terminal pad. As an attempt to remove the solder ball described in Japanese Laid-open Patent Application No. 63-261857, photosensitive polyimide film is formed on the whole surface of a semiconductor chip except terminal regions and is dissolved by an organic solvent later. However, this method is incompatible with semiconductor chips having polyimide as an insulating film.